1. Field of the Invention
The present invention relates to display devices and, more particularly, to a display device utilizing current-driven type light-emitting elements.
2. Description of Related Art
Organic electro-luminescence elements (hereinafter referred to as "organic EL elements") have been conventionally known in which a current is applied to luminescent elements formed on a glass plate or a transparent organic film to drive them for emission.
The configuration of a display device can be simplified by configuring it such that a common part of such organic EL elements is displayed in the form of a matrix as a single display portion.
When organic EL elements as described above are used as light-emitting elements, since the light-emitting element have different display areas, an element with a larger display area has a lower current density per unit area and hence lower emission intensity than those of an element with a smaller display area.
This results in a problem in that variation occurs in emission of light when a plurality of elements are simultaneously driven for emission, which disallows emission display to be performed with visually uniform brightness.
Especially, when a matrix is formed by connecting a plurality of light-emitting elements to one electrode line, although the intensity of the light-emitting elements can be made uniform by connecting light-emitting elements having the same area to the same anode line and setting the amount of the current for each anode line so an to achieve uniform emission intensity, this approach is limited in various ways and is not practical.